Sewing-machine-motor controller



Feb. 17, 1931.. D. HQ cHAsoN 1,792,817

SEWING'MACHINE MOTOR CONTROLLER Filed Aug. 3, 1927 2 Sheets-Sheet 1 N. N INVE TOR ATTORNEY ,2 QZZLM Feb. 17, 1931.- I D. H; CHASON 1,792,317

- SEWiNG MACHINE MOTOR CONTROLLER Filed iu 5, 192? 2 Sheets-Sheet 2 @lxy/"wz WITNESSES By: a

dam ATTORNEY as converted to" an electric sewing machine atented Feb. 17, 1931 UNITED STATES PATENT Q ICE DANIEL H. GHASON, OF ELIZABETH, NEW JERSEY, ASSIGNOR 'IO THE SINGER MANU EAG'JJUEING COMPANY, OF ELrzABETn, 'NEW JERSEY, e e'onroanrron 0E NEW SEWING-MACHINE-MOTOR CONTROLLER Application filed August 3, 1927. Serial No. 210,285;

- In the widespreadapplication of electricity to the various arts, the sewing machine has received its'share of attention, .and various.

devices for the electric drive and control of sewing machines have been made and used. While the growing demand isfor the complete, factory equipped, electric sewing machine, there are in use large numbers of treadle-driven sewing machines which only await the advent of a conveniently applicable and usable form of motor and motor-controller to convert them into electric machines, There has already beenprovided a sewing machine motor adapted for attachment to the well-known family sewing machineso as to become,- in efiect, a permanent fixture or part of the machine, not requiring to. be re-. moved or shifted When the'm'achine is to be put away or made ready'for use. I refer to the electric sewing machine described in the U. S. patent to Diehl Q and Hemlebf No. 1,488,234, of March 25,1924. 7

The usual sewing machine motor-controh lers are of three types, viz., hand-operated, knee-operated, and foot-operated. The hand-operatedcontroller is little used as.v it interferes more or less with the use of the operators hands in presenting and guiding the work to the sewingmachines. The kneeoperated controller is in more general favor,

I and there is practically no objection to the foot-operated controller in sofar as the broad principle I of foot-operation is concerned. Foot-controllers, such as heretofore commonly provided, have however been of the portable type comprising a pedal operated rheostat adapted to rest upon the floor'ad acent thesewing machine table. The difliculty with this type of foot-controller is that it has a tendency to creep or shift its position. Furthermore, it cannot'be placed in a posi tion for'oonven'ientoperation, for the reason that the treadle-plate element ofthe sewing machine'table occupiesthe'floor space where the foot-controller would be of most con- -venient access to the operators foot and where it would be least likely to manifest its creepingtendencyr I I In the ordinary drop-head sewing machine,

by the application of an electric motor and foot-controller, the treadle mechanism of the sewing machine stand has no function except as a potential foot-power drive and,'as above stated, the treadle-plateis in the-way of convenient location of the foot-controller. 7

With the idea of using the conveniently accessible and. operable treadle-plate as a means for operating the motor-controller, it has been proposed to mount the motor-controller:or rheostat on the sewing machine table and connect it by a pull-rod to the treadle-plate, but none of the devices heretofore proposed fills the long-felt want for. a treadle-plate operated motor controller which may be readilyapplied to or removed from the-usual sewing machine table byone not possessed of mechanical skill, and which is of simple and dependable construction and of. neat and inconspicuous appearance. V

The present invention. has for an object to provide a motor-controller to fill the want referred to'and enable the well-known treadle,

driven family sewing machine to'be readily converted 1nto an electric machine. Further objects of the invention will appear in the following description and claims.

According to the present improvement the stand. The straight-pull treadle connection preferably comprises a spring giving the treadle a greater range of movement than is transmitted to the rheostat. Preferably the usual pitman-rod connection between the treadle andbelt-wheel-is disconnected at its project freely through the bearing aperture in the treadle, a stop-member-being secured to the lower end? of the pitman, below the treadle, tolimitthe downward movement of the use of 0th within.

lower. end from thetreadle and allowed to the latter and prevent undue strain of the spring-pull connection referred to.

In the accompanying drawings, Fig. 1 is a front side elevation of the usual family sewing machine as converted to an electric machine in accordance with theinvention. Fig. 2 is a section onthe line 22, Fig. 1. Fig. 3 is a detail View of the detachable hook-connection between the motor-controller and the treadle-plate. Fig. 4 is a view of the motorcontroller casing as applied to one of the legs of the sewing machine stand. Fig. 5 is atop view, partially in section, of the parts shown in Fig. 4. Fig. 6 is a sectional view on the line 6-6, Fig. 1. Fig. 7 is a detail view of the treadle-plate stop carried by the pitmanrod. Fig. 8 is a sectional viewof the usual connection with the treadleplate for footpower drive. Fig. 9 is a plan View of the controller .with'theicasing removed, and Fig. 10 is a side elevation ofthe controller unit with the casing in section.

Referring .more particularly to Fig. 1, 1 represents the usual=drop-head sewing machine table orstand having a wooden top 2, reticulated or ribbed cast-iron end legs 3 and intermediate ribbed cast-iron brace-member 4 pivotally carrying the usual reticulated treadle 5. The ribs of the legs 3 are of repeated .V-contour, as indicated at 3, and the ribs ofthe brace-member 4 are indicated at 4. The "belt-wheel 6 is carried by the crankshaft 7 embraced'by the crank-strap 8 at the upper end oftlie pitman 9, the lower end of which is formed witlra ball 10, Fig. 8, which, for foot-power drive is j'ournaled in a socket in the bushing 11 fitting the aperture 12 in the treadle-plate and internally threaded to receive the concave end of the'bearing-plug 13 which is held in adjusted position by the lock-nut 14.

The sewing head 15 is shown equipped with an electric motor 16, preferably such as disclosed in the patent to Diehl and Hemleb No. 1,488,234, of March 25, 1924. This motor is connected bythe belt 117 to the sewing machine balance-wheel 18. For foot-power operation the motor-belt 17 is removed and the belt 19 running over the belt-wheel 6 is applied to the balance-wheel 18.

For electrical operation there is detachably applied to the leg 3 remote from the belt wheel 6 amotor-controller having a base 20 to the flat back face of which is riveted a plate 21 formed with hooks 22 -shaped to snugly embrace one of the V-ribs 3' of the reticulated leg 3.

Rising from one end of the base 20 is an end-wall 21 having a slot 24 through which passes the pull-rod 25 connected at its inner end to the U-shaped member 26, the ends of the legs of which are joined by the flat member 27. Recovery-springs 28 surrounding the steady pins 29 and the pins 30 carried by the members 26, 27, serve to restore the pull-rod 25 to initial or non-running position with the stop-pin 31 contacting with the endwall 21. The member 26 also acts as a stop by striking the end-wall 21 and limiting the motion of the pull-rod 25 in a direction to compress the springs 28.

Mounted on the base 20 independently of the pull-rod 25 and recovery-spring mechanism 28, 26, 27, is the compression rheostat unit having the usual porcelain body 32 formed with spaced wells or chambers 33 for the stacks of carbon resistance disks 34 which substantially fill the wells 33 and are electrically connected to the terminals 35. The stacks 34 also comprise the compression heads 36 which are bridged by the bow-spring contact member 37 backed by a stiffer spring member 38 substantially in accordance with the disclosure of the patent to D. H. Chason, No. 1,643,292 of Sept. 27, 1927. From the center ofthe bow-spring 37 there extends in line with the pull-rod 25 a second pull-rod 39 having a screw thread end 40 carrying an adjustable nut 41 whose shank 42 passes through an aperture 42 in the bar 27. The aperture 42 has an open side 42" through which the pull-rod 39 may be passed in assembling or disassembling the resistance unit and base 20; the nut 42 being unscrewed part way. A recovery-spring 43 surrounding the rod 39 is disposed between the body 32 and the bow-spring 37. The nut 41 is soadjusted that the bow-spring will be carriedout of contact with the pressure-heads 36 by the spring 43 when the springs 28'are holding the stop 31 inengagement with the end-wall 21 of the base. The various parts on the base 20 are enclosed withina suitable casing 44 having hooks 44 engaging the recesses 44 in one endof the base 20; the end of the casing remote from the hooks 44 has a downwardly extending'lip 44 screwed to the end-wall 21- r The pull-rod 25 is connected by the coilspring 45 to the h ook '46 liavin serpentine shank 47 extending under and over the ribs 48 of the reticulated treadle-plate 5, as shown in Fig. It will thus be seen that the connection between the bow-spring 37 of the rheostat and the hook 46 on the treadle-plate is a straight-pull connection devoid of levers, rock-shafts, cams and the like. The spring 45 permits a greater range of movement of thetreadle-plate 5 than is transmitted to the pull-rod 2.): the operative range of movement of the treadle 5 suitable for nicety of control of the speed of the sewing machine by easily controlled movement of the operators foot. To prevent undue strain of the sow-spring 37 and to free the treadle from the inertia of the belt-wheel 6, the bearing plug 13 and nut 14 are unscrewed and thepitman 9 allowed to pass freelythrough the bushing 11. A stop-member comprising a strip of shect-metal bent to circular form to receive the plug l3, Fig. 7, and having legs 49 clamped together with the screw 50 around the pitman-rod 9 and plug 13, serves as a stop to limit the down movement of the rear edge of the treadle-plate 5 under the pressure of the operators foot. It isto bevunderstood, however, that while it is preferred to disconnect the belt wheel 6 from the treadle 5 for electrical operation, it is not essential that such disconnection be made.

The controller terminals are connected with the cord 51 which extends upwardly to the motor and supply-cord 52; the connections being such that the rheostat and motor are electrically in series relation.

It will be noted that the direction of pull of the rod 25 and connection is in the direc tion of the apex of the particular V-rib 3, Fig. 4, engaged by the hooks 22 which causes the controller to be snugly held in position on v the leg 3 bythe operative forces applied to the controller and without the necessity of Wing screws, clamps or otherfastening de vices requiring'special manipulation to efiect the securing or the release of the controller from the leg% when required.

The invention is not to be understood as limited to the details of construction herein shown and described, as it is obviously susceptible'of material modification within the bounds of the invention defined by the claims. Having thus set forth the nature of the invention, what I claim herein is:

1. The combination with the usual castiron sewing machine stand having end legs,

intermediate brace-member, and reticulated treadle-plate carried by said brace-member, of a sewing machine motor-controller mounted on one of the leg members, a controller operating extension having a serpentine shank detachably engaging under and over certain of the ribs of the reticulated treadle, and an operating pull-connection betweensaid extension and-said motor-controller.

2. A sewing machine motor-controlling mechanism comprising the usual sewing machine stand havinga treadle, a belt-wheel, a

crank-shaft carrying said belt-wheel, a pitman-rod connected at its upper end to said crankshaft and at its lower end extending through an aperture in but disconnected from' said treadle, a motor-controller mounted on said stand, an'operating connection between said treadle and motor-controller, and a stopmember mounted on said pitman-rod below said treadle and-serving to limit the downward movement of the treadle and prevent undue strain of said operating connection.

8. The combination with the usual castiron sewingmachine stand having reticulated flat end legs with V-shaped ribs, intermediate brace-member and treadle-plate carried by the brace-member, of a sewing machine motor-controller including a casing having a fiat'side face, hook-means on said face detachably engaging one of said V-shaped ribs, :1

In testimony whereof, I have signed my name to this specification.

DANIEL H. CHASON.

sof 

